---

	FORUM ON BEER, HOMEBREWING, AND RELATED ISSUES
		Digest Janitor: janitor@hbd.org
		Many thanks to the Observer & Eccentric Newspapers of 
		Livonia, Michigan for sponsoring the Homebrew Digest.
				URL: http://www.oeonline.com


Contents:
  Secondary Fermentation and sugars in beer (Dave Burley)
  Big Teeth and Fuzzy Little Animals,  Long Serving Lines (Dave Burley)
  ENZYMES pt 1 ("Stephen Alexander")
  ENZYMES pt 2 ("Stephen Alexander")
  yeast growth (Bryan Gros)
  Raspberry Hefe ("scott")
  mash thickness (John Wilkinson)
  Deutschland here we come! ("scott")
  beach (Paul Mahoney)
  Partial retraction of long hose (Pat Babcock)
  RE: Equipment for All Grain (Randy Shreve)
  Fw: AHA Problems ("Steven Stacy")


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Date: Fri, 30 Jul 1999 14:29:42 -0400
From: Dave Burley <Dave_Burley at compuserve.com>
Subject: Secondary Fermentation and sugars in beer

Brewsters:

Matt Comstock eschewed the use of secondaries
because he believed the beer from his prinary was
superior.  This got him into trouble with his honey
containing beers because he bottled them within
about 2 weeks directly from the primary and got
beer suitable for launching ships, but too carbonated
for his taste. He asks for advice on how to use a
secondary, since this will also relieve him of the
stress of bottling and brewing at the same time.

Well, in beer,  the so-called "secondary" fermentation
is really a continuation of the yeast fermentation,
unlike Lambic beers and wines in which the secondary
( and also tertiary for Lambics) fermentation is
bacterial in nature.  Both these types of fermentation
share the distinction of proceeding at a much slower
rate than the primary yeast fermentation.  In the
case of beer, it is due to the change in the substrate
from the simple hexose sugars ( like glucose) and
disaccharides ( like maltose) to the higher sugars
( like maltotriose).  There is a distinct change in the
rate as these bigger molecules have a different
mechanism ( I believe) in some cases.  Whatever
the reason, these rates are noticably slower.

On top of that ,the yeast ( depending on the strain)
begin to flocculate and fall out ( or up to the head)
of solution in response to a number of factors.
( See SteveA's recent HBD discussion on flocculation).

These factors include
 1) disappearance of glucose
2) appearance of alcohol
3) water hardness and chemicals added 

   ( specifically calcium)
4) temperature
5) beer viscosity
6) shape and size of the fermenter
7)and other stuff, especially the yeast strain.

Of course, when the yeast fall out of solution,
they cannot continue to ferment very easily
( even though they are still able to function
biochemically),  since their exposure to the wort
is limited. This now becomes an engineering problem.

What's a brewer to do to finish out a fermentation?
In our case, stir or transfer the beer  - including the
yeast - into another container to stir up the yeast
( as they do in some British Midlands breweries)
with very flocculant yeasts and promote the finish of
a fermentation. Test the beer with Clinitest and
when it is constant ( i.e. same reading) or is 1/4%
or less over a three day or so reading, then you
know the beer is finished.  My experience with
my beers is that it takes 4 or 5 days to go from
1/2% to 1/4% Clinitest "glucose" units.  That's
pretty slow compared to the initial fermentation in
which it takes 4 or 5 days to ferment nearly the
whole amount of sugar.  But that is often an
unappreciated fact of just how slow these rates
are near the end of the fermentation.

AlK has commented on more than one occasion
of the travails of Miller Brewing when they started
using a stirred fermentation.  I suspect I remember
that time and it was when I stopped drinking Miller,
only because they changed the formulation and
the "Champagne of Bottled Beers" became a
darker and heavier beer ( only relatively) and I
did not like it. They may have changed their
formulation to compensate for the lower residual
sugars by adding caramel malts - I don't know.
That is no longer a problem, as they now have
control over the minor sugar content by using
chilling and filtration techniques only available
on a large scale in the last couple of decades or so.

Matt, perhaps one of the reasons you prefer the
primary-only beer to one which has been
transfered to a secondary is because you prefer
a little sweetness in your beer. This is not unusual,
since in my opinion a number of popular American
lagers ( so called "draft brewed", "cold filtered"
and the like) have a residual sweetness due to
chilling and early filtration.Since the fermentation
is not finished ( that is still some fermentable
sugars present), this leaves a little bit of sugar in the
beer ( for the same reason you like your primary
better) and to free up a fermenter earlier. These
brewers can get away with it since they can filter
to a microbe free product that is sterile packaged
and often kept cool.  We don't have that luxury
in most cases.The danger is that you may bottle
your beer early and get bottle bombs or at least
overcarbonation, as Matt experienced.

How do you get what you like and still produce
stable bottles?

If you are an all-grainer, just raise your mashing
temperature in the saccharification to a higher
level - say 158F. If you are an extract person, use
some of the "dextrins" supplied by your HB store
to up that perception of sweetness and still finish
the fermentation of fermentable sugars. 


And now to answer Matt's question on how to
handle secondaries.  I wait until the head on the
beer has just dropped ( say 3 to 5 days) and this
(along with about 1/4 of the yeast and other crud
from the bottom) is then carefully siphoned into
a carboy which is closed with a fermentation lock
(bubbler). Any oxygen entrained will be quickly
taken up by the still active yeast and the CO2
generated by trhe fermentaion will also sweep
out the headspace This is allowed to sit for
several weeks - two or three- at fermentation
temperature.

When
the beer starts to look somewhat clear, I begin
the Clinitesting and allow it to sit there until I get
a reading of 1/4% or less before proceeding to
bottle or keg.  Remember to prepare an active
"kraeusen" starter ( see my description in the
archives)  to  get reliable natural  carbonation.
If you cannot get to a stable reading in this time
period ( it may not match my readings with my
beers), try stirring or dropping your beer again
( especially for high OG beers and barleywines).

Hope this long-winded discussion was helpful in
allowing you to understand that a part of brewing
consistently is to control the subtle sweetness
some beers require to be on style and to please
certain drinkers, yet have a bottled or kegged
beer which is stable and properly carbonated.

Keep on Brewin'

Dave Burley

Return to table of contents


Date: Fri, 30 Jul 1999 14:37:53 -0400
From: Dave Burley <Dave_Burley at compuserve.com>
Subject: Big Teeth and Fuzzy Little Animals,  Long Serving Lines

Brewsters:

JackS has heard that a 0.1M ( tenth molar)
hydrochloric acid soak is good for his pH
electrode and "not knowing much about big teeth"
needs to know how to make up this solution. I
don't know if this is the correct solution for your
electrode but here's the solution to your
problem and more.

Actually the story starts with a fuzzy little animal
called a Mole or one gram molecular weight.

In the case of HCl, the hydrogen is one gram
atomic weight and chlorine is 35.5 gram atomic
weights. Add them together in the ratio they
appear in the molecular formula ( in this case
1and1) and you get a gram molecular weight
( or a Mole).

One gram molecular weight of
anything contains the same number of
molecules ( Avogadro's number). In this case
an Avogadro's number of hydrogen atoms
( weighing one gram) reacts with an Avogardo's
number of chlorine (weighing on the average
35.5 grams) to give an Avogadro's number 

of hydrogen chloride molecules weighing
36.5 grams.

Now if you were to add 36.5 grams of HCl and
make up to a liter of water you would have a
solution that contains one Mole per liter or
a 1 Molar solution. Add 3.65 grams to make
up a liter and you would have a
0.1 Molar (tenth molar) solution.

Now how to make up that Muriatic solution you
buy at the pool store to a 0.1 M HCl solution?

Carefully - gloves and glasses.  If the
Muriatic Acid you buy is 35% HCl and you
know the density of the solution ( I think
SG = 1.2) you can either weigh  or measure
volumetrically this stock solution.  Just weigh
out the appropriate amount. If you want
3.65 grams then 3.65/0.35 = 10.428 grams
and dilute this up in water in a liter soda
pop bottle.

To make a smaller amount ( say 100 mls)
I would just add 17 drops of this Muriatic acid
to 100 mls of water.

[20 drops = 1 ml or 1.2 grams of a SG = 1.2
Muriatic acid. (17/20)*1.2 *0.35 =  0.357g in
100 ml solution is 0.1M] 

- ---------------------------------------------
Sorry PatB, despite what others
may find in a bar technician's handbook to
make his life simple ,  the reported fixed
resistance per foot of tubing is NOT a fact.
It is TOTALLY DEPENDENT of the flow rate
of the liquid and other factors in the fluid train
 - including the length and diameter of tubing
and the differential pressure as others have
also attested here.

Given a certain flow rate, then this table
makes some sense, but notice that in this
case the small tubing has to have the same
<flow rate> as the big one.  This an unlikely
situation for a bar in which the flow rate is not
constant, but the head pressure is.
The flow rate changes in response to
tubing length and other resistance points in
the fluid train. This table is very mis-leading

The concept of a fixed pressure drop
per foot of tubing is incorrect from basic
physics and engineering.

Keep on Brewin'


Dave Burley

Return to table of contents


Date: Fri, 30 Jul 1999 15:37:24 -0400
From: "Stephen Alexander" <steve-alexander at worldnet.att.net>
Subject: ENZYMES pt 1

Science content -  page down if your brain overheats on use -

Several questions about enzymes have come up lately

>My original point was this: if a thinner mash provides a greater amount
>of energy to the soup,

I doesn't.  In this context there is no relationship between water and
energy.  Temperature is the measure of the kinetic (and rotational and
vibrational) energy among the starch and amylase molecules, as others have
clearly described.

> and beta is more heat labile than alpha

This means that the temperature at which beta-amylase(BA) significantly
degrades (other conditions being equal) is lower that the temperature of
significant alpha-amylase(AA) degradation.  For example the half-life of BA
in a 1.25qt/lb mash at 65C is ~16 minutes, and alpha-amylase(AA) is
~43minutes.  The  half lives are much much greater at 30C, but a similar
relation hold between the two.

>then wouldn't
>one expect a more ready denaturing of available beta v. available alpha;

Yes, but this is true at all temps including 20C in your malt storage bin
and 75C at mash-out.

===-
I think a little enzyme note is in  order.

Enzymes are proteins, and are created in a nearly direct transcription
process from DNA to RNA to protein.  Enzymes and their remarkable catalytic
activity are a primary expression of genes. These long strings of amino
acids are have extremely complex shape or conformation.  They form spirals
like DNA and amylose, but also fold and turn sharply.  They  forms weak
molecular bonds between the folds.  The various amino acids have distinct
electrical properties and so along the length of the protein the electrical
potential varies.  The internal electrical attractions also determines the
shape of these ribbons of amino acid.

Enzymes just speed up reactions, they are not used up, nor do they supply
energy.  They just make reactions which are already happening very slowly,
suddenly happen much faster.  Imagine a billiard table without pockets
(where would the physical sciences be without billiard analogies?).  The
lowest energy state for the ball is on the floor, while the table is a
higher potential energy state.  The balls usually stay on the table during
normal play, because they don't have the energy to make it over the bumper.
If you supply a lot of kinetic energy then once in a long while a ball goes
over the bumper and hits the floor. Adding enzymes is like lowering the
bumper height.  No energy is added to the balls,  but the rate of change
from high to low energy state is vastly increased.

Hydrolytic enzymes [amylases, glucanases  proteases and peptidases in malt]
require substrate (starch, protein etc) AND WATER. Water is a key reactant
in the breakdown process.  The hydrolysis reaction  breaks a chemical bond
in starch, for example, and one side of the broken bond gets a hydrogen (H)
from water, while the other side gets the hydroxyl group (OH).  So busting
up all the bonds in your malt  actually uses up a little water.

Next we need to consider the kinetic energy amongst the molecules.  The
amount of energy needed to tear apart a protein or starch molecule is
extremely high - like having billiard table bumpers a foot high.  When
enzymes are added the energies required drop by a factor of 2 to 10, but
they are still much higher than the typical energy of a molecule at room
temp.  For example a particular peroxidase enzyme lowers the 'bumper' energy
from 76kJ/mol to 30kJ/mol.  But at room temperature the average molecule has
only about 3-4kJ/mol, and raising the temperature by 10C increases the
average kinetic energy by less than 2%.

Fortunately the energy is not evenly distributed between the molecules.  A
small, but appreciable number of molecules carry the requisite 30kJ/mol for
the reaction above, and many orders of magnitude fewer carry the 76kJ/m
needed for the non-enzymatic reaction.  Also the number of these very high
energy molecules increases almost exponentially with temperature, leading to
the familiar rule of thumb that many reaction rates double per 10C temp
increase.  There are other factors which make this rule imprecise, but the
main points are that the number of reactions with sufficient energy is
vastly increased (often by a factor of 10^6 to 10^10) by the presence of
enzymes.  Also that this number roughly doubles per 10C increase in our
domain of interest (20C to 100C).

If you bring together water, substrate and enzyme - all in the right
orientation and conformation, with sufficient kinetic energy, the hydrolysis
breakdown occurs.  But at what rate ?

TEMPERATURE:
As we have seen, temperature increases cause an almost exponential increase
in the number of collision in which the reaction might happen.  So
temperature is a major factor.  Instead of increasing at 2X per 10C as a
simple analysis would suggest, enzyme reaction rates typically increase from
1.2X up to 3X per 10C.

CONCENTRATION:

The reactant concentrations impact the reaction rate.  Given a solution of
amylase enzyme, an increasing amylose concentration at first causes a near
linear increase in reaction rate, but eventually when enough amylose
substrate is added the enzyme is effectively 'saturated' and can react no
more quickly. The curve this represents and the equations that fall out of
this observation are attributed to Michaelis and Menten of almost a century
past. (see crude graph below)


REACTION RATE
   |
   |            _____-----------------      - Vmax
   |        .
   |      `
   |    /
   |   -
   |  /
   | /
_/_______________________  reactant concentration


Water is a reactant in our mashes too, but since it is also our solvent the
matter is a bit confusing to think about.  For a *fixed* concentration of
amylase and amylose, increasing the water concentration results in a curve
similar to the one above.  However if we just add water without holding the
enzyme and substrate concentrations fixed, then we just end up diluting
these.  In other words a pound of malt thrown in Lake Michigan takes forever
to convert because the enzyme and starch concentrations are so low and not
directly because the water concentration is high.

That is really about it - except of course for the fine print ...

 -S








Return to table of contents


Date: Fri, 30 Jul 1999 15:38:07 -0400
From: "Stephen Alexander" <steve-alexander at worldnet.att.net>
Subject: ENZYMES pt 2

Science content -  page down if your brain overheats on use -

FINE PRINT:

1/  The instantaneous concentration of enzyme changes.  Enzymes go into
solution during the mash-in, and in solution their likelihood of interacting
is higher.  The more interesting factor is the denaturing of enzymes.  When
enzymes break their internal weak fold to fold bonds they lose their shape
and so their effectiveness.  In a few cases this denaturing is reversible -
but this is rare.  The major cause of denaturing in the mash is temperature.
If enzymes are involved in collisions (or vibrations) too energetic then
their internal structures change.  They are still proteins, but they are no
longer enzymes.  Under a fixed set of conditions, the rate at which enzyme
denature due to temperature is akin to the way radioactive material decays,
or the charge on a capacitor bleeds off.  It makes sense to describe it in
terms of a half-life.  A 1.25qt/lb 65C mash (and other conditions of pH
etc), the half-life of beta-amylase was about 16 minutes.  This means that
the first 16 minute mash interval will have twice the activity of the second
interval and four times the activity of the 3rd interval, and so on,
assuming other conditions are constant (which they are usually not).   The
enzyme decay rate with increasing temperature is also exponential in nature,
but is much greater than the activity increase and usually in the range of
6X to 36X per 10C increase !!  This means the half-life time decreases
markedly with temperature increase.

If you 'do the math' you will find that there is an optimal temperature for
a mash enzyme ONLY if you specify the time duration of the mash.  For a 15
minute mash, maybe 70C is optimal for beta amylase (!!), while for a 2 hr
mash perhaps 58C is optimal.

2/ The amylopectin in a mash ties up an incredible amount of the water as
gel and so this water is unavailable for the enzymatic hydrolysis.  Amounts
of water much less that 1.1 qt/lb of malt cause a tremendous drop of in
reaction rate.  This is similar to the 'knee point' in the crude graph
above.  Of course the gel changes throughout the course of a real mash so
this factor is dynamic.

3/ The enzyme activity varies with conditions. The enzyme, as previously
stated, has a precise conformation that is effected by the electrical
charges that it carries.  These electrical attractions cause minor changes
in the enzyme shape which in turn may have a big impact on the enzyme
activity.  Free salt ions or a change in pH can have a profound effect on
the enzymes charges, shape and activity.  Contrary to some previous posts,
these changes are NOT typically denaturing.  They usually effect activity,
but they do not destroy the enzyme.

4/ Some enzymes also have cofactors, additional molecular 'partners' which
either allow or improve the enzyme catalysis.  Each alpha-amylase molecule
for example requires a calcium ion for it's activity.  It is thought the Ca
ions charge effects the enzyme conformation.  Many vitamins and minerals are
enzyme co-factors.

5/ Substrate stabilization.  Increasing the amount of substrate and
decreasing the amount of water often has the effect of making the hydrolytic
enzyme more stable. In the extreme case very dry but starch rich malt, is
kilned at 120C and above - yet the enzymes survive for hours.  In less
extreme cases thick mashes *may* demonstrate greater proteolytic or
beta-amylase activity than expected in a thin mash at the same temperature,
*BUT* the low free water concentration also limits the reaction rate.  I am
aware of this method being used, for example to get a protein rest from
infusion hardware, but generally I think it is of limited value and
difficult to control accurately as compared to time and temperature control
in a step mash.

6/ Product inhibition.  Some enzymes, like beta-amylase can have their
activity inhibited by the presence of their own product (maltose).
Sometimes the product can also stabilize as well as inhibit the enzyme.
Perhaps in a very high gravity low temp mash this has an impact but I doubt
that it is usually a significant factor compared the  temperature denaturing
loss of beta-amylase

7/ Other stuff.  There are a myriad of other effects that are small but may
add up to something.  Pumps and stirrers can denature enzymes through shear
force damage.  Chemical reactions may change the enzyme, proteases and
peptidases may destroy some enzymes (which are proteins).  Extreme pH
conditions may denature.  Of course combinations of the above may have a
synergistic effect.  The 'wrong' pH may make enzymes more susceptible to
shear damage of thermal denaturing.

===
dogma challenged  ...

As a practical matter, the enzyme to starch  & protein ratio's are fixed by
our choice of mash bill.  I personally think that water:grist ratios below
1.1 qt/lb are questionable, and that figures around 1/5qt/lb are probably
near optimal.  Studies show small but real increases in extraction and
enzyme activity to 2qt/lb and even beyond,  but I would reserve these
thinner mashing techniques to cereal mashes where the undegraded
amylopectins require vastly more water.

Any mashing with brewers malt must take into account the fact that not only
is alpha-amylase less temperature sensitive than beta-amylase, but it exists
(in terms of activity) in vastly greater quantities. (~20X)  Because of
this, saccharification rests in mashing should be considered an exercise in
getting just the desired amount of beta-amylase activity.  Sufficient
alpha-amylase exists so that a single infusion rest at 80C(176F) gives
completely normal extract levels, and sufficiently low starch levels to be
considered a complete conversion !! [only at 85C do starch levels rise
dramatically].

 -S








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Date: Fri, 30 Jul 1999 12:49:51 -0700 (PDT)
From: Bryan Gros <blgros at yahoo.com>
Subject: yeast growth

Someone posted:
>There is a very interesting discussion on yeast propagation. They advocate
>incremental feed and continuous aeration of the starter. According to what's
>written there, if you manage to keep the yeast in the logarithmic growth
>phase (not allowing it to switch to alcohol production) you can collect a
>much bigger amount of yeast than traditional step-up methods. Unfortunately
>there are not many details on the exact procedure. There are many references
>to scientific literature, but I have no way to check them.

I have heard this as well. This (the exponential growth phase) is how
yeast is produced commercially. With the right mix of food and oxygen,
yeast is easy to grow.

The problem for homebrewers is that we don't have the equipment to 
constantly monitor the yeast conditions and adjust the oxygen/food. If
you could rig up a way to drop a 1.040 wort into your starter at the
right rate, and be able to adjust the rate on the fly, you could have
your starter ready in a day or so.

The best you can probably do is have an O2 source to bubble into your
starter every so often. I believe George Fix has posted some data 
showing that 1.040 or so wort is just as good as a 1.020 or so wort
(but contains twice the food), and wort produces much better yeast
than sucrose (in terms of attenuation). 

Another thing that helps is an incubator of some kind. If you can
keep your starter near 80F, you get faster reproduction.

If you have a good procedure, you can find a consistent timeline for
making your starter. i.e., start with smackpack on monday with 8 oz.
of wort, feed 1 pt. of wort on tuesday, feed 1 qt of wort on thurs,
decant and pitch on saturday. 

If your brewing schedule is flexible, then a consistent prodedure is
not needed so much, and you brew when the yeast is ready.

Or better yet, just get a bunch of yeast from your friendly brewpub!

===
 - Bryan
    gros at bigfoot.com

  "To live your life it seems,
   is a waste without a dream..."
                          - BoDeans
_____________________________________________________________
Do You Yahoo!?
Free instant messaging and more at http://messenger.yahoo.com



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Date: Fri, 30 Jul 1999 13:30:54 -0700
From: "scott" <Cuckold at cornerpub.com>
Subject: Raspberry Hefe

Have to agree about the lack of brewing talk on the HBD as of late.  Here's
my brewing addition for you all:

3rd allgrain batch, everything working out great.  Haven't gotten around to
testing the water yet, but so far brewed some great hefe's and raspberry
wheats, using a 60% wheat grain bill.

10 gal. batch.  Had large raspberry crop, so at racking time, dropped 2 lbs.
of pasteurized berries in one of the carboys (last year made the mistake of
following a recipe that called for 5lb, it was way too much).  No filter or
mesh screen wringing, just dropped them in.

It turned out great!  Nice berry taste, but not too much.  Light red color,
and absolutely no seeds whatsoever.  At bottling time I did a little
overkill and attach a copper scrubber to the racking cane, but don't think
it was necessary.

So next time, you might try pasteurizing the fruit and just throwing it in.
It worked for me!

Scott and Karin
Richland, Wa.



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Date: Fri, 30 Jul 1999 15:44:35 -0500
From: John.Wilkinson at aud.alcatel.com (John Wilkinson)
Subject: mash thickness

Steve Alexander posted over a week ago (21 Jul) about the effect of mash
thickness and temperature on fermentability of the wort.  This is an excerpt:

>For an hour long mash at various temps and mash
>thickness Hall reports as follows. Each triplet of numbers below represents
>results for a mash thickness of <67%, 39%, 29%> this corresponds with
><0.7, 1.25, 1.7> qt/lb in HB terms.  Mashing temperatures as listed.
>
>Fermentability(%)
>140F    <73.3,  76.1,  76.2>
>150F    <67.4,  71.2,  69.7>
>155F    <64.4,  65.0,  65.3>
 .
 .
 .
>
>Note the highest fermentability is for the 140F/1.7qt/lb mash,....
> The variation in fermentability was primarily due to mash temp, tho'
>thickness clearly was a significant effect..

Would this fermentability be reflected in apparent attenuation?  For instance,
If OG was 1.050 and fermentability was 71.2% would an FG of about 1.0144 be
expected and with the same OG and fermentability of 65% would the expected
FG be about 1.0175?

Also, yeast spec sheets show apparent attenuation numbers of from 67% to 75%.
Why would apparent attenuation depend on the yeast?  It would seem that the
fermentability of the wort would determine that, except for yeasts that were
able to ferment sugars that other yeasts could not.  If one ale yeast has
an expected apparent attenuation of 67% and another of 75% does that imply
that the 67% yeast will leave some fermentable sugars?  I am assuming that the
OG is not such as to produce high enough alcohol levels to inhibit the yeast.

This puzzles me.

John Wilkinson - Grapevine, Texas


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Date: Fri, 30 Jul 1999 13:45:07 -0700
From: "scott" <Cuckold at cornerpub.com>
Subject: Deutschland here we come!

Karin and I are heading back to the old country in sept.  fly to Paris, roam
the countryside, including Normandy before heading to her parents place near
Frankfurt.  I haven't been there in 20 yrs, and you better believe we're
going to stop at every pilstube and cantina along the way.  Her brother has
arranged for personalized tour of the Licher brewery.  True, not a "big
boy", but should be much fun.

anyone know of any must have or see brews or gasthouses along the way from
Paris/Cherbourg/Paris/Frankfurt route?  We plan on staying out of the
touristy places and just mixing with the locals and small towns.  Besides, I
have my own private interpreter!

Thanks,
Scott and Elke
Richland, Wa.
http://www.geocities.com/Paris/Salon/3768/Brewery.html



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Date: Fri, 30 Jul 1999 17:45:52 -0400
From: Paul Mahoney <pmmaho at roanoke.infi.net>
Subject: beach

I will be hitting the beach on Wednesday August 4.  I was hoping for
some information about brewpubs or microbreweries in the Ocean City, Md.
 - Rehoboth Beach, Del. area.  Is anyone familiar with any such
establishments?
Next, I heard that the Wild Goose brewery in Cambridge, Md. was closed
when Frederick Brewing acquired it.  Is that true?  I was hoping for a
brewery tour if it was still open.

Paul Mahoney
Roanoke, Va.

Fill with mingled cream and amber,
   I will drain that glass again.
Such hilarious visions clamber
   Through the chamber of my brain -
Quaintest thoughts - queerest fancies
   Come to life and fade away;
What care I how time advances?
   I am drinking ale today.

(Poe, 1848)





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Date: Fri, 30 Jul 1999 20:37:54 -0400 (EDT)
From: Pat Babcock <pbabcock at mail.oeonline.com>
Subject: Partial retraction of long hose


Greetings, Beerlings! Take me to your lager....

Dave continues with...

> Sorry PatB, despite what others
> may find in a bar technician's handbook to
> make his life simple ,  the reported fixed
> resistance per foot of tubing is NOT a fact.
> It is TOTALLY DEPENDENT of the flow rate

That was the part of the disconnect between your post and my response,
pointed out here in your post and by Jeff McNally in private. The" Bar
Tech's Book" assumes a flow rate. The tubing specs in other catalogs
(non beverage-specific) specify flow rates for each column of data (and
you interpolate between...)

I misread/misinterpreted your post to state that there were no physical
properties OF THE TUBING affecting the pressure drop per foot. My
apologies for the mis-read. But I still have fundamental problems with
both your assertion and with your continued response here. (Note that I do
respect you and your vast knowledge, don't lose sight of that. No
factiousness intended. Statement of fact.) We're all adults here, so I'll
continue... 

> of the liquid and other factors in the fluid train
>  - including the length and diameter of tubing
> and the differential pressure as others have
> also attested here.

Don't forget the material...

> 
> Given a certain flow rate, then this table
> makes some sense, but notice that in this
> case the small tubing has to have the same
> <flow rate> as the big one.  This an unlikely

Why would this be unlikely? Realizing that the flow cannot be adequately
modelled without an analysis of the line lays, the tubing characteristics,
and the impulses of flow at opening of the faucet (doubtful closing would
have much affect, unless immediately reopened), etc. To attempt such an
analysis to the precision we, as engineers, would like to see would be
insanity. When things are grossly out of the planar ordinary, you must -
at least on portions of the system - but few systems require that rigor.
Plus, you absolutely *MUST* make assumptions regarding the liquid (unless 
serving a product as consistent as Budweiser, perhaps). 

Per the flow rate, consider that the barkeep would be mighty upset if the
larger line had the same pressure designated for the narrower line
applied.  He'd never be able to serve what came out (excepting, perhaps,
Guinness through a sparkler head). The point here is that having the same
flow rate no matter what the tubing configuration/applied pressure is
PRECISELY what they want when specifying beer hose. You want the beer to
flow in your glass at a rate that is reasonable - not too pokey, but not
supersonic. And you don't want he beer to out-gas itself along the way. 
Hence, the tables are designed to show a "drop per foot" at a given flow
rate. They are "designed" to either drive you to a serving pressure based
on the lengths involve - for an assumed flow rate (that acceptable one I
cannot remember.  1 gpm?  0.8gpm? Dagnabbit memory!)  or, more reasonably,
to drive a length of hose for a particular serving/carbonation pressure
(should be the same.  Modulating the pressure drop - the line length - in
the system is what allows you to do that.) Miller does an excellent job of
explaining this in "Just Brew It" which. as I recall, is an AHA conference
transcript book. Yes. It's a simplified description of practical data.

Yes, they have no provision for undulating lines laid under the bartop. 
Yes, they have no provision for temperature differentials along the way. 
Yes they have no provisions fo the effects of gravity on the route. They
provide a rule of thumb for the draft system designer to use to lay in a
draft system under typical conditions. This method has been in use and
proven effective for a lot longer than I've been paying attention to it. 

> situation for a bar in which the flow rate is not
> constant, but the head pressure is.
> The flow rate changes in response to
> tubing length and other resistance points in
> the fluid train. This table is very mis-leading

It is misleading ONLY if used without guidance, or for purposes other than
it was intended. It does not specify a pressure or line length. It
specifies a pressure drop per foot at an acceptable serving flow rate. The
pressure you need to maintain to keep your beer properly carbonated at
serving temperature is your serving pressure. You subtract the drops
associated with your keg tap/connector/probe/whatever and your faucet,
then select an ID based on your length requirements. Going long? You need
less drop per foot - select the large ID. Going short? You Need more drop
per foot - select the smaller ID.  Then get enough of that tubing to add
up to your remaining pressure.  Voila. A reasonably balance draft system
without any fourier analysis.  Basic algebra; linearized data. So why does
that bother you so much? (Please don't tell me whether or not fourier
analysis is actually used in fluid flow or I'll digitize you into the
Z-plane using LaPlace transforms. We'll deal with the aliasing later...)

> The concept of a fixed pressure drop
> per foot of tubing is incorrect from basic
> physics and engineering.

But not at an assumed flow rate. The point so obvious to me that I
guess I side-stepped it in my original post. 

Dave, basic physics - true first year basic physics does a lot to
"linearize"  properties and concepts that are best modelled through simple
calculus and complicated differential equations (Yaaagh! Diff-Eq's!). The
linearized representation of these concepts are not invalid. Just less
accurate. Basic Engineering tabularizes incredible amounts of data and
relies on linear interpolation to derive values between listed data
points. The interpolated data is not invalid. Just less accurate. As much
as I'd like to see everyone using higher mathematics, that's the reality,
guys.  This is no different. 

In the pure sense, you're both dead on, but attacking a practical notion
merely for the sake of scientific accuracy is not, in my opinion, value
added. Particularly when we're talking draft systems. Finally, it only
serves to confuse those who are attempting to USE the simplified data when
we engage convoluted arguments to demonstrated how they can be
misinterpreted. 

This is a repeater subject on the HBD, BTW. I respond almost every time it
comes up. That must be a personality flaw. That I miss and leave out a
pertinent point (flow rate) almost every time is DEFINITELY a personality
flaw. What may have been construed as mean-spiritedness in the post
(Whap!) is just my twisted sense of humor (and obvious personality flaw -
one, I hope, Dave and others recognized for what it was. Hmmm. My desire
to spell personality as personallity mus tbe a personality flaw, too). 
I'm not trying to piss in your mash tun, either, gentlemen. I just find
the assertion that simplified, practical data is misleading as irksome as
you find the simplified data. Nuff said. (Of course, as always, you're
welcome to respond.)
 
> Keep on Brewin'

Just startin' back up, brother! Wheeeee! Bottling this weekend, I hope,
too. (I'd keg them, but Kim deems bottling as "quality time". Being we
have so little time together anymore, I have to agree...). You would not
BELIEVE the dust on everything, though. Thank goodness for bottlewashers
(that aren't, I hope, stuck)...

See ya!

Pat Babcock in SE Michigan         pbabcock at oeonline.com
Home Brew Digest Janitor           janitor@hbd.org
HBD Web Site                       http://hbd.org   
The Home Brew Page                 http://oeonline.com/~pbabcock/brew.html

"Back at the mash tun again. Back where the grist is a friend, oh, I'm
back at the mash tun again...."




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Date: Fri, 30 Jul 1999 20:56:37 -0400
From: Randy Shreve <rashreve at interpath.com>
Subject: RE: Equipment for All Grain

Russ Hobaugh asked for advice about inexpensive and effective equipment
in Digest #3096.  Here's my two cents:

I use a brewpot outfitted with the EasyMasher for both mashing and
boiling.
It works great.  Stove top mashing allows you to easily add heat when
you need it.
I also use a home-made motorized mash mixer that works very well.
There are a couple downsides I have discovered to this method.  They
are:
(1) you have to use some kind of pot/barrel to collect the mash runnings
which will need to be transferred back into the pot for boiling (after
you have gotten rid of the spent grains), and
(2) brewing time is chewed up during this transfer.

I don't have the storage space for a three tier system, so I accept this
tradeoff.  I have been doing full volume boils on the stove top for some
time now with very good results.  My average brew day from start to
finish (including clean-up time) is around 7 hours using this method.
Homebrewing on a tight budget is filled with tradeoffs.  Make the most
of what you have - the beer's gonna be great!

Peace and Long Life
Randy in Salisbury, NC
Middle Earth Brewing Company



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Date: Fri, 30 Jul 1999 20:18:18 -0500
From: "Steven Stacy" <stacys at rollanet.org>
Subject: Fw: AHA Problems



- ----------
> From: Steven Stacy <stacys at rollanet.org>
> To: post@hbd.org
> Subject: Re: AHA Problems
> Date: Tuesday, July 27, 1999 7:12 PM
> 
> Just want to post one data point about the AHA.  When I started to make
my own homebrew back in 1980 I had a great struggle.  In those days
information about our hobby was close to null.  I'll admit to knowing about
Zymurgy at that time but didn't inquire about it then.  I spent post of my
brew money trying to make acceptable beer.  I stumbled into a copy of Dave
Line's Big Book of Brewing and moved from Blue Ribbion extract to all-grain
in 1982.  In 1984 I finally sent for a copy of Zymurgy and was hooked.  A
lot has changed since then.
> 
> I still have that first issue, and though is was slim, it was like I had
found a group of of kindred spirits.  I immediately joined (member #4548)
and stuck with the AHA until the infamous Charlie-puts-a-walk-in
cooler-in-his-new house issue that came out in 1995.  That was enough for
me and I quit along with  many others.  Subsequently Karl Lutzen gave me a
copy of the AOB's Return of Organization Exempt from Federal Tax for 1995
and it shows CP making a cool 114K in total compensation.  (want a copy?
let me know) 
> 
> In January of this year, I found out the NHC would be in KC.  I am the
past president of the Missouri Assocation of Serious Homebrewrs (MASH) and
wanted to help the KC Biermeisters with what ever we could,  our club
helped out with a couple of hospitality sessions and I joined the AHA once
again.  I should also add that MASH did have prior positive experence with
Brain on  the Big Brews days of the past two years.  I was very happy to
meet Brain and had a very positive chat with him and others about how the
AHA seemed to be getting it back together. 
> 
> Now with Brain's dismissal its clear to me what's going on at the AHA. 
I've had it!  It's time that the members take the AHA out of the AOB.  Let
Charlie write his crap for the New Brewer and let the AHA stand on it's
own.  I'll bet the AOB would fold in a minute.  
> 
> Steven Stacy 
>  


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